According to WENN:

An argument between Lindsay Lohan and girlfriend Samantha Ronson resulted in a smashed window at the DJ’s home, according to reports.

The incident occurred on Saturday (14Mar09) morning after Lohan spent Friday (13Mar09) night partying with pals at hotel Chateau Marmont in Los Angeles, before paying a late night visit to the home of actor Jack Nicholson.  Lohan left Nicholson’s house in the early hours of Saturday and headed to Ronson’s residence, reports People.com.

The DJ arrived home a few hours later and the pair allegedly began to argue loudly before a neighbour called the police.  Shortly afterwards a side window of the house was smashed, sending glass flying across a path, and officers arrived at the property.   A source tells WENN, “The police were called in by a neighbour after a loud argument between Lindsay and Sam, which could be heard out on the street.
“At one point, something went flying through a side window, shattering glass on the side walkway of the house.

“LAPD officers pounded at the front door but Lindsay or Sam did not open the door.”  A representative for Lohan could not be reached as WENN went to press.

Police at the scene:

Photos:  WENN.com