The City of Berkeley has confirmed that, as of now, no person or entity is being investigated in relation to the balcony collapse last week that killed six students and injured seven others.

City officials have closed their investigation and the Berkeley Police Department is not carrying out any criminal investigation in relation to the tragedy.

The District Attorney's office has "reached out" to the City Council and has said that it "will begin looking at the matter", but stressed that no formal investigation has been launched at this time.

Deputy District Attorney for Alameda County in California Teresa Renick told RTÉ News it would be "premature at this point" to say that there was any investigation.

As of now, the only recourse available to those involved and to the families is to launch civil actions.

The City of Berkeley released the results of its investigation into the incident yesterday and found evidence of "severe" and "extensive" dry rot in the balcony.

The authority also confirmed that the number of people on the balcony at the time was not a factor in the collapse.

Dry rot was the only contributing factor, said Eric Angstadt, Director of the City's Planning and Development Department. 

He said the lack of ventilation around the wood used in the construction was an issue and that is why they were going to bring about emergency regulations to change this for all future buildings and would make the new building codes retroactive.

In the ten-page report, they described how investigators on the scene had discovered that the wooden joists extending out from the building which supported the balcony decking had extensive dry rot.

The report shows that city officials began their investigations within two hours of the collapse and immediately noticed what appeared to be severe dry-rotting on the jagged wooden joists that remained in the building wall, which had detached from the balcony deck. 

When they returned later that morning in daylight, and viewed them from a platform lift, they reported these joints were extensively rotted at the points where they had snapped.

Mr Angstadt said city officials were not shocked at what they saw, and said the dry rot was at an advanced stage but that it can spread quickly.

Later on the day of the tragedy the collapsed balcony was removed and the following day the second balcony attached to the unit beneath it was also removed.

Tests were carried out on the other two balconies at the complex but they had a slightly different design and tests showed no sign of distress or water damage so they remained in place.

An analysis of the building's original plans shows that they were in compliance with all of the requirements of the time, some of which have been upgraded since, and that all mandated inspections were carried out as required.

As a result of these findings, the Building and Safety Division has recommended that the council adopt new and modified regulations as an emergency to enhance the safety of all existing and future buildings.

In particular they have recommended better ventilation requirements for outside areas that are exposed to the weather, allowing them to dry out if they suffer water damage.

They have recommended that this new regulation would be retroactive, would become effective within six months of being passed by the council, and that it would be subject to further inspection every five years.

However, as of now, there are no active investigations into the tragic incident, so there is currently no potential to hold anyone criminally responsible for the loss of life and serious injuries caused.

Once the office of District Attorney Nancy O'Malley has begun looking at the matter, it may launch an investigation of its own.

Any investigations carried out for civil actions may produce evidence of neglect or safety breaches which could merit the opening of a criminal investigation at a later date.

Meanwhile, the funerals of Niccolai Schuster and Olivia Burke, two of the six victims of the Berkeley balcony tragedy, have taken place in Dublin.

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Even though the building was constructed in accordance with relevant building codes and all of the inspections had been carried out, there was still this issue of dry rot.

Although no person or entity is now being investigated, those involved in the tragedy and their families can still take civil actions, and more details may arise from these actions.

However, as of now, the balcony that had been removed and the balcony underneath it have been returned to the owners of the building so the city’s investigation is finished for now.

The city of Berkeley will have emergency legislation brought in, which will change regulations regarding outside areas such as balconies.

The Mayor of Berkeley has said he expects a lot of civil actions will follow, and he also may be sued personally. However, he said he is confident in how this investigation was carried out.