The family of a man beaten during an altercation with Denver police said they may remove him from life support.Thomas Charles Armstrong, 37, has been in critical condition since the encounter with Denver police early Friday morning.Police said they received a call at about 1 a.m. about a man in the middle of the street screaming for help at the top of his lungs."He was screaming, 'Help me. Help me,' And he was screaming like he was dying or something," said witness Lori Sykes.As an officer approached the man, the man began to attack the officer, fighting and struggling with him, police said.As more officers arrived at the scene to help, the man was restrained and quit breathing.He was rushed to University Hospital, where he has been on life support.Ironically, Armstrong has been a critic of police and his family claimed he has been a target of police for years because of his criticisms.According to the watchdog group Denver CopWatch, Armstrong's injuries were the result of excessive force."Trained professional police officers should be capable of restraining an unarmed suspect without causing severe head injuries or damage to internal organs," a statement from CopWatch said.Police said the amount of force used against Armstrong was justified."The members of the Denver Police Department are not going to respond to outlandish allegations from those that are pursuing their own agenda and are driven by emotion and speculation," said Detective Virginia Lopez, a police spokeswoman. "It is unfortunate that there has been no talk from anyone about individuals being held responsible for their own actions such as illegal use of extreme narcotics ... and we all know what they can do to a person's rational actions and thinking."Members of Armstrong's family have urged community members "to support their call for justice and answers" by joining them at a 6 p.m. protest Monday outside the District 2 Police Station in northeast Denver.