When members of the Alto family showed up to vote on the San Pasqual Indian reservation on Sunday, they were met by tribal security guards and San Diego County sheriff's deputies who prevented them from entering the building where the election was taking place.

That was an apparent violation of their civil rights, according to a federal official.

But a spokesman for the sheriff's department said Tuesday that the deputies were not the ones who decided to keep the tribal members from voting; the tribal government did.

"The standing, elected government of that tribe decides," said Sgt. Bob Bishop, with the Valley Center substation. "They decide who is going to be allowed into the meeting, we don't."

The tribe is embroiled in a long-standing dispute over whether members of the Alto family belong in the tribe.

The federal government issued a tentative ruling in November siding with the family. But some members of the tribal government, including Chairman Allen Lawson, and members of the San Pasqual enrollment committee say the Alto family members, about 59 of them, are not official San Pasqual Indians.

Keeping officially enrolled tribal members from exercising their right to vote could be a violation of their civil rights, said Jim Fletcher, superintendent of the Bureau of Indian Affairs for Southern California.

Fletcher said on Monday that he is waiting for the official results of the election and written accounts from people to look into the matter.

American Indians have had a long history of disenfranchisement. They were first granted American citizenship and the right to vote in 1924 with the passage of the Indian Citizenship Act. But some American Indians have been prevented from voting by various means in several states, including requirements to be "civilized."

The Voting Rights Act of 1965, which was passed in large part to protect blacks from systematic discrimination at the polling place, also gave American Indians protections from discrimination.

On Sunday, the San Pasqual tribe held its election to decide who would represent the tribe's 300 members on its government council, which consists of a chairman, vice chairman, secretary and two other council members.

Angela Martinez-McNeal, the tribe's former secretary and a member of the Alto family, said her family was informed in advance through a letter that they would not be allowed to vote. She said her family was illegally prevented from voting and plans challenge the election.

"We told them, we're tribal members," Martinez said. "But they wouldn't hear it."

Bishop said the department has a contract with the tribe to provide extra deputies during special events, such as tribal meetings. He said there were 12 deputies outside the meeting to "keep the peace."

A group of about 10 people approached the gate where the tribal security stood guard, Bishop said.

When members of the Alto family arrived at the gate, they were turned away by tribal security guards because they were not on the roster of tribal members provided to the guards by the San Pasqual government, Bishop said.

Several people tried to enter past the gate by sidestepping the security guards. But when one of the family members attempted to rush past the security guards, deputies were asked to assist in removing them from the property.

A video posted by the Alto family members on the Web site YouTube shows a deputy telling those who tried to get in that they would be arrested for trespassing if they did not leave.

Bishop said no one was arrested and no one was cited in the incident.

"All we did is preserve the peace," Bishop said. "We assisted them in removing people when they (security guards) got pushed past by about three or four of them and went into the parking lot."

Contact staff writer Edward Sifuentes at (760) 740-3511 or esifuentes@nctimes.com.